Python: reflect inheritance between VLM and LLM decoded results (openvinotoolkit#1519)

Author: ilya-lavrenov

src/python/openvino_genai/py_openvino_genai.pyi

@@ -1745,7 +1745,7 @@ class UNet2DConditionModel:
         ...
     def set_hidden_states(self, tensor_name: str, encoder_hidden_states: openvino._pyopenvino.Tensor) -> None:
         ...
-class VLMDecodedResults:
+class VLMDecodedResults(DecodedResults):
     """
     
         Structure to store resulting batched text outputs and scores for each batch.

src/python/py_vlm_pipeline.cpp

@@ -112,7 +112,7 @@ void init_vlm_pipeline(py::module_& m) {
         .def("get_prepare_embeddings_duration", &ov::genai::VLMPerfMetrics::get_prepare_embeddings_duration)
         .def_readonly("vlm_raw_metrics", &ov::genai::VLMPerfMetrics::vlm_raw_metrics);
 
-    py::class_<ov::genai::VLMDecodedResults>(m, "VLMDecodedResults", decoded_results_docstring)
+    py::class_<ov::genai::VLMDecodedResults, ov::genai::DecodedResults>(m, "VLMDecodedResults", decoded_results_docstring)
         .def(py::init<>())
         .def_property_readonly("texts", [](const ov::genai::VLMDecodedResults &dr) -> py::typing::List<py::str> { return pyutils::handle_utf8(dr.texts); })
         .def_readonly("scores", &ov::genai::VLMDecodedResults::scores)